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Thursday, January 5, 2012

ORA-845: MEMORY_TARGET not supported on this system on linux in oracle 11g or ORA-04031

This is for initialization parameter MEMORY_TARGET or MEMORY_MAX_TARGET value.

This value cannot be greater than the shared memory filesystem (/dev/shm) on you linux system. Or This error may also occur if /dev/shm is not properly mounted. Make sure in your df -k output filesystem shmfs is mounted

To know the shared memory filesystem issue following command.

# df –k /dev/shm

To resolve the current error, increase the /dev/shm file size.

For example:

# mount -t tmpfs shmfs -o size=60g /dev/shm

To make this change permanant, add an line in /etc/fstab like following:

shmfs /dev/shm tmpfs size=60g 0

In sun solaris operating systemcheck the value of “shmsys:shminfo_shmmax” in following location.